The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Engine assemblies typically include intake and exhaust valves that are actuated by valve lifters. The valve lifters may be operable in multiple modes to provide varying lift durations for the intake and exhaust valves in order to improve engine performance, such as increasing fuel economy and power output. Operating parameters of the engine may be adjusted based on the actual operating mode of the valve lifters. Engine performance may be reduced if the valve lifters do not transition to a commanded mode.